Method for treating a body of a polluted porous medium

• US 7,334,965 B2
• Filed: 04/19/2006
• Issued: 02/26/2008
• Est. Priority Date: 04/20/2005
• Status: Expired due to Fees

• Current Assignee: National Sun Yat-sen University
• Original Assignee: National Sun Yat-sen University
• Inventors: Yang, Gordon C. C.
• Primary Examiner(s): KRECK, JOHN J
• Application Number:
  US11/406,436
• Publication Number:
  US 20060237029A1
• Time in Patent Office: 678 Days
• Field of Search: 977/903, 405/128.75, 588/313
• US Class Current: 405/128.75
• CPC Class Codes: B09C 1/08 chemically
• CPC Class Codes: B09C 1/085 electrochemically, e.g. by electrokinetics
• CPC Class Codes: Y10S 977/903 for conversion, containment, or destruction of hazardous material

Abstract

A method for treating a body of a polluted porous medium, includes the steps of: preparing a reactive solution containing nanoparticles; injecting the reactive solution into the body of the polluted porous medium so as to decompose pollutants in the polluted porous medium by reacting the nanoparticles with the pollutants; and applying an electric field to the body of the polluted porous medium so as to enhance transporting effect of the nanoparticles in the body of the polluted porous medium.

Claims

1. A method for treating a body of a polluted porous medium, comprising the steps of:

preparing a reactive solution containing nanoparticles;

injecting the reactive solution into the body of the polluted porous medium so as to decompose pollutants in the polluted porous medium by reacting the nanoparticles with the pollutants; and

applying an electric field to the body of the polluted porous medium so as to enhance transporting effect of the nanoparticles in the body of the polluted porous medium.

2. The method of claim 1, wherein the reactive solution is prepared by adding a reducing agent into an aqueous solution of an iron salt to reduce iron ions into iron nanoparticles, followed by adding a dispersing agent into the mixture to permit suspension of the iron nanoparticles in the reactive solution.

3. The method of claim 2, wherein the iron salt is a compound selected from the group consisting of:

ferric chloride, ferrous chloride, ferric sulfide, ferrous sulfide, ferric nitride, ferrous nitride, ferric bromide, ferrous bromide, and combinations thereof.

4. The method of claim 3, wherein the reducing agent is selected from the group consisting of:

sodium borohydride, potassium borohydride, lithium borohydride, sodium carbonate, potassium carbonate, sodium hydroxide, potassium hydroxide, lithium hydroxide, methanol, ethanol, lithium aluminum tetrahydride, ammonium ion, hydrazine, citric acid, sodium citrate, potassium citrate, and combinations thereof.

5. The method of claim 4, wherein the dispersing agent is selected from the group consisting of polyvinylalcohol, polyacrylic acid, polyvinylpyrrolidone, polyethyleneimine, polyethylene oxides, sodium polyphosphate, sodium polyacrylate, terraalkylammonium halogenides, sodium dodecyl sulfate, sodium hexametaphosphate, and combinations thereof.

6. The method of claim 2, wherein the iron nanoparticles have a particle size ranging from 1 to 100 nm.